This invention relates generally to hypodermic syringes of the kind that are commonly used for injecting a medication into a body or for aspirating a liquid (such as blood) from a body; more specifically, it relates to a protective device that is usable in connection with such syringes in order to protect a user from being stuck with a used needle.
Injury to users of hypodermic syringes has become of increasing concern, now that it has been well established that an accidental needle stick (involving a contaminated needle) can be enough to pass along blood-transmitted viruses such as hepatitis, herpes and acquired immunodeficiency syndrome (AIDS). Medical literature is now replete with warnings to medical personnel who handle hypodermic syringes to avoid even the slightest puncture of the skin with a used needle. Furthermore, there is an on-going risk to everyone who might come into contact with a used needle, including medical personnel and those who are involved in disposing of medical waste, etc.
The recognized risk of accidental needle sticks has prompted several persons to propose technical solutions to the problem of safe handling of used syringes and their associated needles. It is believed that the safest proposals are those which do not involve removal of the needle from the body of the syringe; to this end, it has been proposed to leave the needle in place and simply slide a tubular cover or sleeve over the needle after it has been used, so as to avoid any inadvertent contact with the needle's tip. Examples of such constructions may be found in U.S. Pat. Nos. 4,976,702 to Andrews et al. entitled "Syringe Needle Guard" and 4,998,920 to Johnson entitled "Protective Assembly For Hypodermic Syringe Devices." But while others have proposed at least some solutions, it is believed that a construction that involves the simplest and most direct action on the part of the user will be the best action. And any construction that involves a combination of required motions--such as push and twist--is not likely to be as safe as one that requires only a single motion. Hence, it is an object of this invention to provide a hypodermic syringe apparatus that has a protective sleeve that can be carried by the syringe in a stowed position where it does not interfere with normal use of the syringe--and then moved to an operative position with a single, straight-line motion.
It is another object to provide a hypodermic syringe apparatus which can be easily manufactured and assembled, but which offers the dependability of a much more sophisticated structure.
Another object is to provide an essentially fail-safe protective shield for a used needle--as long as the syringe apparatus is not subjected to the kind of deliberate abuse that could be applied with a sledge hammer or the like.
These and other objects will be apparent from a reading of the following specification and the claims appended thereto, as well as reference to the several figures of the drawing that are attached hereto.